• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.352-354
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• 1995

The optical and electrical properties of High Speed AlGaAs infrared LED by using metal wet etch process instead of metal lift-off process are investigated. The power out increases when metal contact is patterned by wet etch process. Forward voltage and Reverse voltage for metal wet etch process represent higher value than the metal lift-off process. The aging effect of power out also indicates good results with wet etch process. The wet etch process for metal contact reveals reliable LED device properties.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.130-139
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• 1999

In order to manage the wet end chemistry on paper machines, our goal is to control sub-processes through which we can influence the entire wet end operations with maximum effect. The most important sub-processes are: consistency, ash, and chemistry. The management of these three main groups is based on on-line maesurements and automatic control. This paper presents a new wet end management platform, a new analyzer. This new analyzer utilizes a modular structure and modem software. It is part of a new paper machine concept. The controls of this concept are feedback and feedforward solutions that control retention, consistencies, ash, and charge, resulting in a more stable wet end (30...80%), more uniform paper, and better rnnability.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.11
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• pp.1049-1058
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• 2001

The performance and design analysis for a NWD cooling tower using a combined wet and dry type fill are numerically investigated and compared with the experimental results. The Stoecker's method is applied to the wet section and LMTD or NTU-Effectiveness method to the wet and dry sections. The efficiency ratio of the NWD cooling tower to a wet type crossflow cooling tower is 59.34%. The predicted result shows a good agreement with the experimental data within 1.4% error. Plume abatement is far better with a NWD cooling tower than a counterflow cooling tower. It costs less than a conventional wet/dry tower because the finned exchanger is eliminated. This method also leaves out complexity in structure and Intricacy in operation.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.3
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• pp.243-250
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• 2019

The nanosecond laser assisted ablation have been investigated. The biocompatable polymer PMMA was employed as the target material and the two distinctive surface conditions were test. The first surface condition is a dry surface for which the target surface is exposed to air and the second surface condition is the wet surface for which the target surface is covered with dehydrated water. The ablation volume, the laser induced acoustic wave, the laser induced plasma were investigated for both wet and dry condition. The nanosecond laser pulse ablatied more on the wet surface compared to the dry surface. The enhanced ablation of wet surface is attributed to the confined acoustic wave and the laser-induced plasma in the liquid layer.

• Journal of Sensor Science and Technology
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• v.30 no.1
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• pp.10-14
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• 2021

Wet etching is more economical than dry etching and provides a uniform etching depth regardless of wafer sizes. Typically, potassium hydroxide (KOH) and tetra-methyl-ammonium hydroxide (TMAH) solutions are widely used for the wet etching of silicon. However, there is a limit to the wet etching process when a material deposited on an unetched surface reacts with an etching solution. To solve this problem, in this study, an apparatus was designed and manufactured to physically block the inflow of etchants on the surface using a rubber O-ring. The proposed apparatus includes a heater and a temperature controller to maintain a constant temperature during etching, and the hydrostatic pressure of the etchant is considered for the thin film structure. A corrugation membrane with a diameter of 800 ㎛, thickness of 600 nm, and corrugation depth of 3 ㎛ with two corrugations was successfully fabricated using the prepared device.

• Journal of Nutrition and Health
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• v.29 no.3
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• pp.278-285
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• 1996

Contents of insoluble(IDF), soluble dietary fiber (SDF), and total dietary fiber(TDF) of 30 foods which are consumed commonly by 80 Koeran male college students were determined by Prosky and colleagues' enzymatic-gravimentric method. Foods with highest intake frequency were rice, Kimch'i, and red pepper powder. TDF, IDF, and SDF contents of rice were 0.96, 0.59 and 0.37g/100g wet wt., respectively and tose of Kimch'i were 3.07, 2.19 and 0.88g/100g wet wt., respectively. Red pepper powder contained high amount of TDF(39.37) and IDF (33.13g/100g wet wt.). The TDF content of the 30 foods ranged from 0.70 to 39.37g/100g wet wt. Red pepper (39.37), dried laver(31.36), and dried sea mustard (37.77g/100g wet wt.) contained high amounts of TDF. The IDF content of the 30 foods ranged from 0.13 to 33.13g/100g wet wt. Red pepper powder (33.13), dried laver(15.55) and sesame(15.43g/100g wet wt.) contained high amounts of IDF. SDF of the 30 foods ranged from 0.01 to 25.66g/100g wet wt. Dried sea mustard(25.66), dried laver(15.81), coffee powder (13.17), and garlic(8.72g/100g wet wt.) were good sources of SDF. % ratio of SDF to TDF of the 30 foods was lower than 50% except soybean curd(94.27%), coffee powder (88.93%), garlic(86.17%), dried sea mustard(67.94%), and dried laver(50.41%). It is recommended to increase intake of seaweeds in order to supply TDF adn SDF properly.

• Korean journal of food and cookery science
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• v.17 no.4
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• pp.373-379
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• 2001

In an attempt to introduce paprika in wet noodles for improved organoleptic and other quality characteristics, the juices of orange paprika was added as a raw ingredient for wet noodle at 0(control), 15, 30, 45, and 60%(v/w). Overall, the cooked wet noodles containing 15 to 60% paprika juices showed higher sensory scores than control(noodle without Paprika juice), and the acceptabilities for color and overall preference of the products were significantly(p＜0.01) higher at the addition levels of 45% and 30 and 45%, respectively. The intensity analysis for the organoleptic quality characteristics of wet noodles with orange paprika juice showed that as the addition levels increased, there were significant(p＜0.001) increase in the values of acceptances for color and flavor of the products, but not in the tenderness and chewiness. Other quality characteristics like water absorption ratio, weight, volume, and turbidity of the broth after cooking of wet noodles increased in values as affected by the addition of paprika juices. In the Hunter's colorimetric characteristics of the products, the decreased lightness(“L”) along with the increased redness(“a”), yellowness(“b”), and ΔE were caused as the amounts of orange paprika juice increased in wet noodles. For toughness, no significant differences(p＜0.001) were noticed among the samples as measured by Waner-Bratzler blade attached to Texture Analyzer. The results of this study suggested that adding orange paprika juice to wet noodles, most preferably at 45%, increases the acceptance and organoleptic qualities of noodle by affecting the color and flavor of the final products.

• KSBB Journal
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• v.22 no.4
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• pp.244-248
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• 2007

The treatment of a model wastewater containing high concentration, 10 $g/{\ell}$, of phenol in an integrated wet oxidation-aerobic biological treatment was investigated. Partial wet oxidation under mild operating conditions was capable of converting the original phenol to biodegradable organic acids such as maleic acid, formic acid and acetic acid, the solution of which was subjected to the subsequent aerobic biological treatment. The wet oxidation was carried out at 150$^{\circ}C$ and 200$^{\circ}C$ and the initial pH of 1 to 12. The high temperature of 200$^{\circ}C$ and the acidic initial condition in the wet oxidation led to effluents of which biodegradability was higher in the subsequent biological oxidation process, as assessed by chemical oxygen demand (COD) removal. Homogeneous catalyst of $CuSO_4$ was also used for increasing the oxidation rate in the wet oxidation at 150$^{\circ}C$ and initial pH of 3.0. However, the pretreatment with the catalytic wet oxidation resulted in effluents which were less biodegradable in the aerobic biological process compared to those out of the non-catalytic wet oxidation at the same operating conditions.

• Journal of the Korea Fashion and Costume Design Association
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• v.21 no.1
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• pp.181-189
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• 2019

The washability, redeposition, fill power, and fabric damage of wet cleaning and dry cleaning solvents were measured to identify the optimal type of washing that would increase washability while maintaining dimensional stability. The soiled fabric is a polyester cotton blend and the types of soil were wine, blood, make-up and sebum with carbon black. Petroleum and silicone solvents were used in dry cleaning. Results from this study are as follows. First, detergency is significantly influenced by the type of washing and type of soil. Wet cleaning is superior to dry cleaning. Wet cleaning shows a strong washing performance against hydrophilic soils, whereas, dry cleaning is stronger against hydrophobic soils. Second, redeposition is significantly affected by the type of washing, fabrics, and soils. Redeposition occurred little on cotton during wet cleaning, but showed a high rate for nylon. However, when the two types of fabric were dry cleaned, redeposition occurred on both types. Third, the fill power of duck-down is very affected by the type of washing. Resilience is the best in wet cleaning; and in dry cleaning, petroleum solvents showed a higher resilience when as compared to silicone solvents. Last, the level of fabric damage to cotton fabrics is highly influenced by the type of washing. Wet cleaning damages cotton fabrics significantly more than dry cleaning. For dry cleaning, petroleum solvents damage these fabrics slightly more than silicone solvents. In conclusion, the type of soil must initially be identified to determine the optimal type of washing. Special caution is required when textiles with particulate soil and nylon are washed. When considering the resilience of duck-down clothing, wet cleaning is more appropriate than dry cleaning. Dry cleaning, especially when using silicone-based solvents, is more suitable than wet cleaning for maintaining the shape of clothing.

• Transactions of Materials Processing
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• v.14 no.9 s.81
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• pp.785-790
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• 2005

High-speed multi-pass wet wire drawing has become very common for production of high-carbon steel cord because of the increase in customer demand and production rates in real industrial fields. Although, the wet wire drawing process is performed at a high speed usually above 1000m/min, greater speed is required to improve productivity. However, in the high-carbon steel wire drawing process, the wire temperature rises greatly as the drawing speed increase. The excessive temperature rise makes the wire more brittle and finally leads to wire breakage. In this study, the variations in wire temperature during the multi-pass wet wire drawing process were investigated. A multi-pass wet wire drawing process with 21 passes, which is used to produce steel cord, was redesigned by considering the increase in temperature. Through a wet wire drawing experiment, it was possible to increase the maximum final drawing speed to 2000m/min.